SH7785 Datasheet, PDF (982/1692 Pages) Renesas Technology Corp – 32-Bit RISC Microcomputer

19. Display Unit (DU)
19.4.14 Upper-Left Overflow Display
For each plane, a display start position in memory (PnSPXR, PnSPYR) and display size
(PnDSXR, PnDSYR) can be set arbitrarily, so that by combining and using these registers, areas
overflowing the upper-left relative to the monitor origin (upper-left corner) can be displayed
without overwriting display data in memory.
For a picture of size (DSX, DSY) and with start position (SPX, SPY), by setting the size to (DSX-
ΔX, DSY-ΔY) and the start position to (SPX+ΔX, SPY+ΔY), the ΔX part overflowing on the left
side and the ΔY part overflowing on top can be displayed. At this time, the display position
(PnDPXR, PnDPYR) is fixed at 0.
Display data in memory
Display area start address
Monitor screen
Monitor origin
SPX
SPY
DSY
DSX
DSY
DSX _Monitor
(DPX,DPY)=(0,0)
Overflow display
SPY + ΔY
SPX + ΔX
DSY - ΔY
DSX - ΔX
ΔY
DSY - ΔY
ΔX DSX - ΔX
Monitor
(DPX,DPY)=(0,0)
Figure 19.11 Schematic Diagram of Upper-Left Overflow Display
Rev.1.00 Jan. 10, 2008 Page 952 of 1658
REJ09B0261-0100